Light-emitting element, method of forming the light-emitting element, and display device

Abstract

A light-emitting element comprises a first semiconductor layer, an active layer provided on the first semiconductor layer, a second semiconductor layer provided on the active layer, an electrode layer provided on the second semiconductor layer, and an insulating film around outer peripheral surfaces of the first semiconductor layer, the active layer, the second semiconductor layer, and the electrode layer, wherein the active layer includes a cover layer including a plurality of quantum dots, and the first semiconductor layer, the active layer, the second semiconductor layer, and the electrode layer are sequentially stacked in one direction to form a shape of a rod.

What is claimed is: 
     
         1 . A light-emitting element comprising:
 a first semiconductor layer;   an active layer on the first semiconductor layer;   a second semiconductor layer on the active layer;   an electrode layer on the second semiconductor layer; and   an insulating film around outer peripheral surfaces of the first semiconductor layer, the active layer, the second semiconductor layer, and the electrode layer,   wherein:   the active layer comprises a cover layer comprising a plurality of quantum dots, and   the first semiconductor layer, the active layer, the second semiconductor layer, and the electrode layer are sequentially stacked in one direction to form a shape of a rod.   
     
     
         2 . The light-emitting element of  claim 1 , wherein the light-emitting element is formed in a shape of a cylindrical rod or a hexagonal rod. 
     
     
         3 . The light-emitting element of  claim 1 , wherein a diameter of the rod is in a range of 0.2 μm to 1 μm. 
     
     
         4 . The light-emitting element of  claim 1 , wherein the plurality of quantum dots and the cover layer comprise In x Ga 1-x N, where x is 0.1 to 0.3. 
     
     
         5 . The light-emitting element of  claim 4 , wherein an indium (In) content of the plurality of quantum dots is different from an indium (In) content of the cover layer. 
     
     
         6 . The light-emitting element of  claim 5 , wherein the In content of the plurality of quantum dots is greater than the In content of the cover layer. 
     
     
         7 . The light-emitting element of  claim 1 , wherein the plurality of quantum dots are spaced apart at random intervals. 
     
     
         8 . The light-emitting element of  claim 1 , wherein a thickness of each of the plurality of quantum dots is in a range of 1 nm to 5 nm. 
     
     
         9 . The light-emitting element of  claim 1 , wherein a size of each of the plurality of quantum dots is in a range of 1 nm to 500 nm. 
     
     
         10 . The light-emitting element of  claim 1 , wherein the active layer has a structure in which a plurality of cover layers, each of the plurality of cover layers comprising a plurality of quantum dots, are stacked. 
     
     
         11 . A method of forming a light-emitting element, comprising:
 forming a buffer layer on a base substrate;   forming a first semiconductor material layer on the buffer layer;   forming a cover layer comprising a plurality of quantum dots to form an active material layer on the first semiconductor material layer;   forming a second semiconductor material layer on the active material layer;   forming an electrode material layer on the second semiconductor material layer;   forming a light-emitting element core by etching the first semiconductor material layer, the active material layer, the second semiconductor material layer, and the electrode material layer;   forming an insulating film around the light-emitting element core; and   separating the light-emitting core and the insulating film from the buffer layer.   
     
     
         12 . The method of  claim 11 , wherein the forming the active material layer comprises forming the plurality of quantum dots by lowering the temperature while forming the cover layer on the first semiconductor material layer. 
     
     
         13 . The method of  claim 12 , wherein the plurality of quantum dots are formed at a temperature of more than or equal to 600° C. to less than 680° C. 
     
     
         14 . The method of  claim 11 , wherein
 the light-emitting element core comprises a first semiconductor layer, an active layer, a second semiconductor layer, and an electrode layer, and   the insulating film is around outer peripheral surfaces of the first semiconductor layer, the active layer, the second semiconductor layer, and the electrode layer.   
     
     
         15 . The method of  claim 11 , wherein the light-emitting element core is formed in a shape of a cylindrical rod or a hexagonal rod. 
     
     
         16 . A display device comprising:
 a substrate;   a first electrode and a second electrode on the substrate spaced apart from each other, the first electrode and the second electrode extending substantially in parallel to each other;   an insulating layer on the first electrode and the second electrode;   light-emitting elements on the insulating layer and aligned on the first electrode and the second electrode; and   a first connection electrode connected to first end portions of the light-emitting elements and a second connection electrode connected to second end portions of the light-emitting elements,   wherein:   each of the light-emitting elements comprises a first semiconductor layer, an active layer on the first semiconductor layer, a second semiconductor layer on the active layer, an electrode layer on the second semiconductor layer, and an insulating film around outer peripheral surfaces of the first semiconductor layer, the active layer, the second semiconductor layer, and the electrode layer,   the active layer comprises a cover layer comprising a plurality of quantum dots, and   the first semiconductor layer, the active layer, the second semiconductor layer, and the electrode layer are sequentially stacked in one direction to form a shape of a rod.   
     
     
         17 . The display device of  claim 16 , wherein the light-emitting element is formed in a shape of a cylindrical rod or a hexagonal rod. 
     
     
         18 . The display device of  claim 16 , wherein
 the plurality of quantum dots and the cover layer comprise In x Ga 1-x N, where x is 0.1 to 0.3, and   an indium (In) content of the plurality of quantum dots is different from an indium (In) content of the cover layer.   
     
     
         19 . The display device of  claim 16 , wherein
 a thickness of each of the plurality of quantum dots is in a range of 1 nm to 5 nm, and   a size of each of the plurality of quantum dots is in a range of 1 nm to 500 nm.   
     
     
         20 . The display device of  claim 16 , wherein the active layer has a structure in which a plurality of cover layers, each of the plurality of cover layers comprising a plurality of quantum dots, are stacked.